Carburetor



J. P. GILLIGAN ET AL cARBUREToR July 8, 1930.

Patented July 8, 1930 UNITED STATES PATENT OFFICE JAMES P. GILLIGAN Arm- LUTHER .r. wnrr uoan, or 'romroo, onro, essreuons or ONE-FOURTH T0 WARD MCMILLEN Ann ONE-FOURTH r0 WENGEL L. cou'rcnunn,

BOTH OF TOLEDO, OHIO Application filed. April 7,

Our invention relates to vaporizer vacuum devices for use with internal combustion engines and, more particularly, to means adapted to control the feeding of a hydrocarbon or a volatile liquid fuel directly from its source, intimately admix it with air in the proper proportion to effect a propercombustion mixture, and deliver the resultant mixture to the engine manifold for combustion purposes.

With our device, the amount of air and the amount of fuel are independently regulated and are directly under the control of the mixture controlling mechanism. Thus, though No. 679,029, filed December 6, 1923. i

Figure 1 is a plan viewof the structure which we have shown and preferably employed to carry out our invention.

Figure 2 is a side elevation of the structure shown in Figure 1 wherein a portion of I the fuel bowl and vaporizer manifold is cut away, the fuel mixing box is removed and certain of the parts are shown in section and shown in partial diagrammatical representation, members 42 and 55, in particular are shown further apart, in Figure 2 than in Figure 1 for a more convenient showing of the elements.

Figure 3 is a; vertical sectional view taken on line BB of Figure 1, looking in the direction of the arrows as shown.

Figure 4 is. a vertical sectional view taken on line A-A of Figure 1, looking in the direction of the arrows as shown.

Figure 5 is a detail view showing the entrance end of the fuel mixing box 17 which I is shown in Figures 3 and 4.

Figure 6 is a detail view showing the exit CARBUBETOR V 1924. Serial No. 704,607.

end of the fuel mixing box 17 which isshown in Figures 3, 4 and5.

Figure 7 is a longitudinal sectional view of the fuel mixing box 17 shown in Figure 5.

Figure 8 is a plan view of the tongue 20 shown in Figures 3 and 4.

, With particular reference to the drawings,

our' invention may comprise .a vaporizer manifold 1, having a flanging portion 2 for attachment to the engine manifold. An inlet pipe 3 is removably secured to the manifold 1. v

A choker valve 4 is mounted-on a shaft 5 and is manually controlled througha lever 6 secured to the shaft 5 by the pin 7. A projection 8contacts with the stop 9 in its closed position.

In the vaporizer manifold 1 is a fuel mixing box 17 provided with an irregularly shaped mixing chamber 23, the entrance to which is circular with the inner walls converging to a rectangular shaped portion, as

shown in Figures 5, 6 and 7. This box 17 I is provided with an opening 18 in itsbase connecting with a conduit 19 serving as a fuel chamber and shaped so'that the vapor fuel issuing therefrom is directed toward the exit of the fuel box 17 and the engine manifold.

A tongue or flap valve 20'is carried on the shaft 21. This valve is rectangular in shape (see Figure 8) and is so positioned that the air entering through the inlet pipe 3 will,

at all times, pass below it into the chamber A of the manifold 1. g

An extension arm is engaged, at times, by the cam 25. tends, at all times, to fall, by gravity, toward its substantially closed position.

The valve 20 raises until the valve arm 24 strikes the cam 25. The degree of opening of the valve regulates the-speed. The cam 25, carried by the shaft 26, carries a manually operated lever 27, which controls the limit ofmovement of the flap valve 20.

When the engine is started and ogerated at an idle speed, the valve 20 will beraised until its arm 24 contacts with the cam 25,

establishing a, minimum size passage past valve 20 to the engine manifold as well as a minimum size fuel mixingchamber.

The free end of the valve 20 a A depending head 28, integral with the vaporizermanifold 1 is .of the shape of the top of the fuel bowl so as to serve as a cover therefor.

The fuel-mixing box 17, the-fuel bowl 30, a gasket 31 and the vaporizer manifold 1 are rigidly held together by the conduit stem 32' i screwed into the fuel mixing box 17, as at 37,

anal by the gasket and nut 34 at the other en A heating jacket 38, with inlet 29 and outlet 40, isprovided to preheat or to maintain at constant temperature the fuel in the bowl 30.

A vacuum control valve casing 42. is located in the top of the bowl 30, as shown in the plan view, Figure 1, its lower end is adapted to receive one end of the pipe or tube 43, as shown in Figures 2 and 4. The other end of this pipe or tube 43 is connected to a vacuum passage 41. The end of the tube 43 projects into the, vacuum control valve chamber 45 to form a vacuum control needle valve seat or metering base 44 controlled by the valve 47. Thus any raw fuel, is prevented fromeventually finding its way through the vacuum passage 41 to the engine manifold. A passage 46 connects to the interior of the bowl 30. Thus communication between the engine manifold and the interior of the bowl 30 is restricted more or less and the rate at which the desired degree of vacuum is to be produced in the bowl 30 is adjusted and fixed. To predetermine the quantity of fuel within the bowl 30,-and maintain the quantity constant at all times, we provide the float 48 carried by a rocker arm lever 49 which is pivoted to the top of the bowl at 50. A horizontally extending arm 51 engages and controls the movement of the fuel control valve 52, carried and guided by the fuel control valve plug 53 screwed into the cover of the fuel bowl 30, as shown in Figure 1. Its top portion is cupped or recessed to form the cavity 54 internally threaded at the top to receive the coupling 55 which carries the fuel line leading to the fuel supply tank. A strainin screen 56 is provided. The fuel contro valve 52 is of the floating type, bein unseated by gravity,'and is winged or uted {:30 piargiait passage of the fuel past it intothe ow To provide means for'feeding the desired minimum amount of fuel at the minimum low engine speed and to increase the speed by increasing the amount of fuel fed to the mixing chamber we rovide an adjusting'nut 57,

- which'we term t e low speed adjusting nut,

adapted to be adjustably screwed into the cover of the bowl 30 as at 58. An opening is provided through its center, as shown in Figures 2 and 3, and a depending tube 60 is attached to its bottom which extends downwardly. into-the bowl 30 and below the level of fuel therein. A fuel metering pin 61 passes through the said opening in the adjustmg nut, this metering pin 61 being guided by said adjusting nut 57 so that a portion of it extends out from and above. the bowl 30 and the other portion extends down into the bowl 30 and beneath the levelof fuel therein. The metering pin 61 is threaded a greater portion of its length and the outwardly extending portion of this metering pin is adapted to receive a stop nut 62, a high speed adjust ing nut 63 and lock nut 64. The mwardly extending portion of this metering pin 61 passes downwardlythrough the tube 60 and has its extreme lower end pointed to form a needle or pin valve. A spring 65 tends to hold the needle valve at its lowermost position permitted by the stop nut 62. A valve seat 67 is provided for the needle valve 61 so that the fuel passage into the conduit 19 may be regulated. 4

In carrying out our invention, we, preferably, first adjust the metering pin 61 so that the desired minimum amount of fuel will be admitted to the conduit 19 whichserves as a fuel chamber-past the metering end of the pin 61. The low speedadjusting nut flange .59 is provided with notches which are engaged by the spring lock 83. The object of this arrangement is to hold the low speed adjusting nut in its adjusted position.

To provide means for automatically increasing the amount of fuel fed directly in proportion to the increase in speed desired, we employ a cam 68 mounted on'the extending portion of the shaft 56', which is opposite the lever 27. the lever 69 which is pivoted to the vaporizer manifold as at 70, as shown in Figures 1 and 3. The opposite end of the lever 69, is bifurcate and engages a groove in the high speed adjusting nut 63 in such a manner as to permit vertical movement of the stem 61 without restriction. Thus when operating at a low speed, the parts above described remain stationary; but as the lever 27 is moved downward to permit the tongue or valve 20 to open to a greater-extent and increase the speed. of

the engine, the cam 68 comes in contact with the ad acent portion of the lever 69, moving it downward, thus permitting a greater amount of fuel to enter the fuel passage 19 within a given period of time. It is thus apparent that the extent to which the tongue or valve 20 is permitted to open determines the degree of opening of the fuel inlet 67 and,

This cam 68 is adapted to engage consequently, determines the amount of fuel supplied to the conduit or fuel chamber and the vaporizer manifold 1 to form the desired combustible mixture; It will be noted that the cam 68 and the cam 25 are carried on the same shaft 26 so that asingle movement of the lever 27 causes a resultant movement of the cams 25and 68. Thus, a common means controls both the admission of air and fuel for the formation of the combustive mixture and both the increase and decrease in the amount and rate of supply of the fuel and the air are made relatively to each other. Independent air adjustments may be made by loosening the cam clamp 78 and revolving the cam about the shaft 26, and independent fuel adjustments may be made by adjusting the cam 68 on the shaft 26, adjusting the high speed adjusting nut 63 and low speed adjusting nut 57. I

High speed adjustment is made without in any way afiecting or disturbing the low speed adjustment which has already been made.

We provide means for stabilizing the de- "gree of vacuum within the bowl and for maintaining it substantially uniform and constant at all times b admitting atmospheric air through the ody of the fuel, in restricted amount. Thus we provide 'an air inlet valve casing 72 removably secured in the cover of the bowl by the threaded portion '73. It'has an opening passing through it,

the lower portion of which is adapted to receive an air tube 74 which extends downwardly into the bowl .30 below the level of the fuel at all times. The top portion of the air valve casing 72 is internally threaded to receive an air inlet needle valve 75, communicating with the tube 74. The needle valve controls the flow ofair from the air inlet 76 into the tube 74, and may be locked in its adjusted position by the lock nut 77. With the above construction, it is seen that the atmospheric air in restricted amount enters the tube 74 and passes into the body of the fuel and then rises to the surface, forming bubbles which rise and burst due to the expansion of the air therein. The air inlet 76 is alwa s of such size that the How of air to the ha y of the fuel in the bowl 30 is always at a lesser rate than the exhaust of the air from the bowl 30 whereby there is always a partial vacuum within the bowl 30 above the fuel.

The exit to the passage 18- leads into an increased velocity zone through which the incoming air for combustive purposes must pass. The area of this velocity zone is determined by the degree of opening of the tongue or valve 20. Thus, at low speed the velocity zone is of a minimum area, while this area is increased as the creased. We provide the passage 79 in the stem 32 leading from the bottom of the fuel bowl for draining the fuel from the bowl 30. This passage is closed by the screw plug 80 and gas-' ket 81. A temporary filling plug 82 is provided in the top of the bowl 30.

' By reference to the foregoing descri tion,

it can be seen that the parts describe may bevaried in form and arrangement without departing from the scope of our invention.

The suction effect of the engine cylinders in starting draws in air from the bowl 30 and speed of the engineis in-' y thereby produces a partial vacuum therein. At this time, assuming that the bowl 30 is not filled with fuel, and the free end of the float 48 is down, the atmospheric pressure,

in the main supply tank, forces the fuelv through the fuel supply pipe into the coupling 55 and past the valve 52 into the bowl 30. When the predetermined fuel level is obtained in'the bowl 30, the float control closes the fuel valve 52.

The fuel in a vapor or gaseous state enters the mixing box 17, where it is directed toward the chamber A. At this time, with the engine operating, the valve 20 is raised, as far as the cam-25 will permit, so as to provide an active portion of the mixing chamber 23 which is of the proper area to efiect the desired mixture dependent upon the speed to be attained. When the engine is not operating, raw fuel enters the conduit or fuel chamber 19 and assumes the same level as the fuel in the bowl 30 and serves as a priming charge when starting the engine.

To increase the speed the lever 27is moved downward, the cam 25 is rotated permitting the valve 20 to open to a greater extent and supply valve we may insure the exact and proper ratio of fuel to gas for every speed because the contour of a cam face may be so designed as to give these ratios whereas with other forms of valve operation these ratios cannot be maintained.

Our invention is further provided with such fuel feeding adjustment that the use of fuels which are less volatile, than gasoline and the like, is made possible.

Our carbureting device is simple in con-- struction, easy to maintain in operative condition and'adjustment and cheap to manufacture. g Having thus described our invention, what we claim is: v

1. v In a carburetor, the combinatlon of a mixlng chamber rectangular in cross-section for a portion of its length, the remainder of its length being frusto-conical, and a rectan vgular flap valve mounted to swing in the rectangular portion of said mixing chamber.

2. In a carburetor, the combination of a mixing chamber rectangular in cross-section for a portion of its length, the remainder of its length being frusto-conical, a flap valve mounted to swing in the rectangular portion of said mixing chamber, and a fuel inlet open- 13. A carburetin'g device comprising a mixing chamber, a float chamber, means for connecting, the interior of said float chamber with a source of fuel supply, means for-creat-' -ing apartial vacuum in said float chamber to draw the fuel thereinto from the source of 4 supply, a conduit serving as a fuel chamber conduit and means for regulating the flow of fuel from said float chamber to said fuel and extending from the interior of said float chamber and from below the level of the fuel therein into said mixing chamber,'and a conduit leading from the atmosphere into said float chamber and to a point below the level 'of the fuel in said float chamber, means for regulating the amount of atmospheric air ad mitted into said float chamber through said chamber and the flow of mixture through said mixin chamber jointly.

4. A carl iureting device comprising a mixing chamber located within the fuel vaporizer manifold of an internal combustion engine, a float chamber carried upon such manifold, means for connecting the interior of said float chamber with a source of fuel supply,

a conduit leading from the interior of such manifold to the interior of said float chamber for creating a partial vacuum in said float chamber to draw the fuel thereinto from a source of supply, a conduit serving as a fuel chamber and extending from the interior of said float chamber and from below the level of the fuel therein into said mixing chamber, and a conduit leading from the atmosphere into said float chamber and having its air delivery end at a point below the level of the fuel in said float chamber, an adjustable valves for regulating the amount of atmospheric air admitted into said float chamber through said conduit andmeans for regulating the fiowof fuel from said float chamber to said fuel chamber and the flow of mixture through said mixing chamber jointly.

5. In a carburetor, the combination of a mixing chamber which decreases in area towards its delivery end, a free swinging flap valvemounted to swing in such decreasing area gortion of said mixing chamber to control't e passa e of the mixture to the motor, and means adjustable to positively limit the opening of said flap valve to any desired extent. a

6. In a carburetor, the combination of a mixing chamber which-decreases in area in the direction'of the air flow, a free swinging flap valve mounted to swing in the decreasing area 'ortion of said mixing chamber to control t e assage of the mixture to the motor, a fuel in ct opening in the wall of said chamber adjacent the free end of said valve, and

means ad'ustable to positively limit/the opene51 i g of said flap valve to any desired extent.

7. In a carburetor, the combination of a mixing chamber which decreases in area in the direction of the air flow, a free swmgmg flap valve mounted to swing in the decreasing area ortion of said mixing chamber to control t e passage of the mixture to the motor, a fuel inlet opening in the wall of said chamber adjacent the free end of said valve, means adjustable to positively limit the opening of said flap valve to any desired extent, and an unobstructed passageway from said flap valve to the motor.

In testimony whereof we aflix our signa1 

